Apparatus for watermarking paper.



Patented Feb.21,191'1. s snnn'rskgngg'rk f J i J 2% JVQW dfi v W. K.TROTMAN.

APPARATUS FOR WATBBMARKING PAPER.

- APPLICATION FILED MAR 24, 1908.

1 J fqgi. 1

W. K. TROTMAN. APPARATUS FOR WATERMARKING PAPER,

APPLICATION YILIID MAR. 24, 1908.

Patented Feb. 21, 1911.

2 EHEBTB-BHEST 3.

. \Vatermarking Paper. of which the followv and rings.

v and fiat frames (wove or laid) used for that more removable sectionscarrying the water? 'bodying the present invention belongs to forwatermarking paper comprises the com- -covering at such spaces beingsoldered.

LUNITED s trnsPAtrENT OFFICE.

- WALTER KNOWLES TROTMAN, OF WOOD GREEN, LONDON, ENGLAND.

' Arman-Ares Fox WATERMARKING PAPER.

Application filed March 24,

To all whom it may concern:

Be itknown that I. 'arxrnn Kxownns 'lno'ratax. a sub ect. of the King ofEngland. residing at \Yood Green, London.

Imgland, have invented certain new and useful Improvements in Apparatusfor This invention, relates to improvements in apparatus forwatermarking paper. namely. the dandy rolls (wove. laid and spiral-laid)purpose. In my previous United Ftates Patent No. 821-206 I havedescribed a dandy roll the cylindrical portion of wlnch has one ormarking device and the apparatus emthesamc type. In the arrangement described in my prior patent. the cylindrical portion of the dandy rollhad a space therein and asection of backing carrying a detachable orother gauze covering was arranged to fit. into the space in the backing.but in the present invention the backing (either of a dandy roll or tiatframe) is made in the ordinary waycomplete. comprising forexamplc (inthe case of a dandy roll) a shaft carrying a series of rings withlongitudinal wires or rods thereon having a spiral backing sheet woundon the rods According to this invention an apparatus' bination with apermanent backing of a gauze covering having one or more removablesections carrying the waternnn'kiug devices. The gauze covering hasspaces therein and is permanently attached to the backing andprojections and rece ses are provided both on the backing and on theremovable gauze sections and are arranged to engage one another so as toretain the sections in position. In constructing a dandy roll inaccordance with this invention. the. permanent backing is made up in anyusual way. The wire gauze covering having spaces therein is permanentlysecured to the backing, the circumferential edges of the fused orotherwise secured to the usual rings of the baekingi and positioningdevices are provided on the removable gauze sections and on the backingso that the sections can be accurately placed in position in .the spacesSpecification of Letters Patent.

therein when in use.

Patented Feb. 21; 1911. 1903. Serial 170,422,945.

in the covering and can be securely held In the accompanyingdrawings:Figures l to 4 illustrate one method of carrying'this inventioninto effect on a dandy roll having a laid covering. Fig. 1 is anelevation partly broken away.' Fig. :2 is a tran verse section on theline 22 of Fig;

1: and Figs. 3 and l are enlarged perspec tive views of details. Fig.is. an elevation partly broken away. and Fig. (3 is a transverse sectionon the line tt of Fig. 5. showing a method of carrying this inventioninto ettect on a dandy roll having a wove covering.

Referring first to Figs. 1. '2. 3, and 4. the main framework of the rollis constructed as usual and consists of a central shaft A having fixedthereon circular ends platesB and a series of circular open disks C. Thewire gauze covering, (in this case a laid covering) is secur d to thedisks in any usual way and the covering consists of longitudinalwires l)secured together by tine interlaced wires 'l') constituting the laidwires and secured also to the rings C. space is leftin the wire gauzecovering at the place where the removable section is to occur and thecut ends of the wires of the covering are soldered. fused. brazed. sewnor otherwise secured to the rings C of the backing. Alongside the rings0 to which the cut ends are solder :l are fixed half rings C to serve assupports for the removable gauze section.

The removable gauze section F having the watermarking device thereonterminates at its endsin a twist or stiti'ening wire F. (constitutingpart of the laid wires in the complete covering. as shown in Fig. 4).Projecting from the longitudinal edges of the removable sectioniF areshortstifi wires G a rranged to be insertedmiderneath the longitudinaledges of the fixed covering. The rings C of the backing and also thehalfrings C are provided with a series of little pins ll arranged toproject into the edges of the removable section so that the removablesection is held in position during use. it will be seen from Fig. 3 thatthe removable section is prevented from moving out radially by 2 fjf984,618

section, the distance between the sets of pins being such that thesection is held accurately in position so as virtually to form part ofthe covering as a whole.

The method of applying the removable section is as follows :-The shortstifi' wires 1 G at one edge of the removable section are insertedunderneath the longitudinal edges of the fixed covering in such aposition that the little pins H engage the first longitudinal Wire ofthe removable section F. The short stifi' wires G at the opposite (orsecond) longitudinal edge of the removable section are also insertedunderneath the corresponding edge of the fixed covering and theremovable section is then gently stroked or rubbed so as to cause thelongitudinal wire at the second edge to ride over the corresponding pinsH and the removable section is then securely held in posi tion. r

In order to detach the removable section for the purpose of substitutinga' section having a difierent watermark, it is only necessary to raisethe longitudinal wire at one edge of the section off the pins H and thento pull the short stifl' wires G out of engagement 'ith the fixedcovering. To

facilitate this, sliding fingers J may be' provided on some of the ringsC immediately under one edge of the removable see tion and these slidingfingers may be op- ,e -atcd by eccentrics J on a rotatable longitudinalrod J operated from the end of the dandy roll by a rotatableknob orhandle J. a

Referring to Figs. 5 and 6 which illustrate a dandy roll having a wovecovering and embodying this invention, the roll comprises a hollow shaftA, end plates B and a series of circular open disks (1.. To theperiphery of these disks is attached the cylindrical frame of the rollconstructed of longitudinal rods K upon which is wound (preferablyspirally) a stout wire L with spaces between the convolutions. Thiscircumfcrential wire L is soldered, sewn, or otherwise secured to thelongitudinal rods K. The shaft A,'disks C, rods K and wire L constitutethe backing of the dandy roll. Upon this backing is secured a wire gauzesheet M forming the outer surface of the roll. A section of'tlie..\viregauze covering N carrying the watermarking devices thereon is removablefrom the roll. In this arrangement the removable section has stiffencrsconsisting of little metallic plates 0 at its longitudinal edges. SlotsP are then cut in the spiral backing sheet of wire L and also if need beslots Q. may be cut in the rings C near the edges of the spaces in thecovering. The stiff edges 0 of the vnovable section are inserted intothese slotsa P Q, and secured in position there. In the arrangementillustrated in Figs. 5 and .6, the stiffening plates 0 have slots 0therein and hooks or snail cams R attached to two rotatable longitudinalrods S having rotatable knobs S at the end of the roll are arranged toenter the slots 0 so that when the removable section N is placed inposition with the plates 0 projecting into the slots I O, and when thelongitudinal rods S are rotated so as to bring the hooks R intoongageme'nt with the slots 0, the removable section is firmly seemed inposition. To replace one removable section by another carrying adifferent watermark, it is only 8 necessary to turn the hool-z's Root ofengagement- With the slots 0 when the removablesection will'be free.Instead of the metal plates 0 stiffened edges of wire or other devicemay be used. S5

The invention has been described in its application to a dandy rollhaving a central shaft and disks thereon but the. invention 15 equallyapplicable to a dandy roll the backing of which is constructed in anyother usual manner for example to a dandy roll having a backingconsisting of a perforated metal sheet or a backing consisting solely oflongitudinal rods and spiral windings.

It is to be understood that the details of arrangement and constructionmaybe varied without departing from this invention.

ll'hat I claim as my invention and desire to secure by Letters Patentis 1. In an apparatus'for watermarlci 1g pa- 00 per the combination of acomplete and permanent backing, a gauze covering permanently secured tosaid backing and having a space therein, a removable gauze sectioncarrying the watermarking devices and 1 adapted to fit into said space,and projections and recesses on the backing and section to engage oneanother and retain the section in position.

2. In a dandy roll the combination of a complete and permanentcylindrical backing comprising a shat t and a series of circular disksthereon, a cylindrical gauze covering permanently secured to saidbacking and having a space therein, a removable gauze section adapted tofit into said space, and projections and recesses on the backing andsection arranged to engage one another and retain the section inposition.

In a dandy roll the combination of a shaft. a series of circular diskspermanently secured thereon, longitudinal rods pcrnianently secured tosaid disks, a backing sheet formed of wire wound on the rods andpermanently secured thereto and having longitudinal slots therein, awire gauze sheet permanently secured to said backing sheet and having aspace therein. a removable section of gauze sheet adapted to fit ins-aidspace, s'tifl'cncrs at the longitudinal edges of said section arrangedto project into the slots Y sheet M permanently secured to said back- 7V ing sheet and having a space thereln, areand means for securing thestiffeners to the back ng to retain the section 121 posltlon.

4. In a dandy roll the combination of a shaft A, a series of circulardisks C permanently secured thereon and having slots Q, in theircircumference, longitudinal rods K permanently secured to said disks, aback-e ing sheet formed of wire L wound on and permanently secured tothe rods K and having longitudinal slots P tl1ere1n,a wire gauze movablesection of gauze sheet adapted to the siotsiin the sti eners O of theremovable 20 gauze section.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing Witnesses.

WALTER KNOWLES TROTMAN.

W'itnesses:

\VILLIABE H. BALLANTYNE, HARRY B. BRIDGES.

